The status and whereabouts of at least five main Pakistani suspects linked to the Mumbai [Images] attacks remain a mystery, with an anti-terrorism judge remanding only one accused to the custody of the Federal Investigation Agency.

The anti-terrorism court Judge Sakhi Muhammad Kahut on Monday remanded Hamad Amin Sadiq, a Lashkar-e-Tayiba [Images] activist described by the Pakistani authorities as the "main operator" behind the Mumbai incident, to the custody of the FIA for 15 days.

There was no official word on the status and whereabouts of the five other suspects, who, the interior ministry chief Rehman Malik had said, were in the custody of authorities.

Though Malik had not named these suspects during a news conference last week, sources told PTI they included senior LeT operatives Zakiur Rehman Lakhvi and Zarar Shah, who have reportedly been named in the Indian dossier submitted to Islamabad [Images].

Sadiq was remanded to the FIA's custody by Judge Kahut during proceedings held in a makeshift court set up in the high-security Adiala Jail in Rawalpindi.

Sadiq was brought to the prison in an armoured vehicle and his face was covered with a mask. The media was not allowed to photograph him.

In its First Information Report, the FIA filed charges against Sadiq under the Anti-Terrorism Act, Pakistan Penal Code and the Prevention of Electronic Crimes Ordinance.

FIA inspector Zahid Akhtar and special public prosecutor Chaudhry Zulfiqar told the judge that authorities wanted information about Sadiq's accomplices involved in the Mumbai incident.

The officials told the judge that Sadiq was an active member of the LeT and was accused of facilitating and abetting the Mumbai attacks in collusion with other suspects.

Official documents presented in court said Sadiq, who hails from Rahim Yar Khan in southern Punjab province in Pakistan, was arrested in Faizabad area of Rawalpindi on Sunday.

However, interior ministry chief Malik had said during his news conference that Sadiq was arrested much earlier in Karachi.

Media reports on Saturday had said that an anti-terror court had remanded at least six suspects to the custody of the FIA. Judge Kahut has taken exception to these reports and told media persons that his court could issue a legal notice in this regard.

Diplomatic sources indicated that Pakistani authorities were deliberately being vague about the status of the suspects due to security concerns and ongoing investigations aimed at uncovering more details about the planning of the Mumbai attacks.

The sources also said that the western diplomats, including those from the United States, had been told by Pakistani authorities that the suspects would be brought to trial in an anti-terror court.

The authorities kept the media guessing about the presentation of the suspects in court on Friday and Saturday before finally producing Sadiq in court.

Though a special cell has been arranged at the Adiala Jail for the suspects, prison Deputy Superintendent Muhammad Feroze Kilyal said they had not been brought there.

FIA officials and the interior ministry spokesman have declined to comment on the status of the suspects and the probe into the Mumbai attacks, saying they had been directed by their seniors not to speak to the media on these issues.